The present invention relates generally to attachments for tractors and more particularly to a blade attachment wherein the blade is mounted in a removable manner intermediate the front and rear pairs of tractor wheels.
To enhance the usefulness of tractor type vehicles a wide variety of accessories is provided for temporary attachment to same. Included in such attachments is a blade attachment with the blade being positioned forwardly or rearwardly of the tractor chassis by an adjustable support assembly. All blades so mounted incur a common disadvantage during use, the disadvantage being that, during tractor travel over uneven ground, vertical displacement of the blade from a desired course is accentuated by reason of the blade being offset a considerable distance from the axis of such movement. These up and down excursions of the blade during tractor movement result in non-uniform grading of the surface being worked and, if severe, can inhibit tractor travel by excessive blade penetration. A further disadvantage of placement fore or aft of the supporting vehicle is the visibility problem as the blade is largely obstructed by the forward part of the tractor or, conversely if rear mounted, requires that the tractor operator conduct a grading operation looking to the rear to monitor blade operation. Ideally, the blade is disposed intermediate the tractor wheels similar in placement to blade disposition on a motor grader.
While the prior art includes disclosures proposing the mounting of a blade on a tractor amid the chassis ends, the support structure for such mounting is extremely complex by reason of the limited space resulting in a costly tractor attachment and an attachment that is both difficult to mount and remove from the vehicle. Further, the mechanism for tilting and locking of the blade transversely to the tractor centerline is complex rendering the known blade attachments both costly and difficult to mount and remove.
To the extent the prior art is known, blades mounted intermediate the tractor wheels rely largely on manual effort for vertical position by reason of the fact that the central location of the blade is remote from any powered appendages of the tractor. While such manually positioned blades may be acceptable for some very small or garden type tractors, such is not acceptable on medium to large size tractors capable of performing road grading operations.